1. Field of the Invention
The present invention relates to a projector unit for projecting an image which is formed by an optical modulator onto a screen or a wall.
2. Description of the Related Art
In these days, in many cases, video projectors are used as a projector unit for projecting images transferred from a personal computer or a video recorder.
The video projector as the projector unit has a high-intensity light source, a color wheel for sequentially converting white light from the light source into red light, green light and blue light, and a light source side optical system for irradiating the red light, green light and blue light that have passed through the color wheel on to an optical modulator such as a DMD and is configured to project an image beam formed by the optical modulator on to a screen or the like by a projection lens, which constitutes a projection optical system.
The optical axis of a lens optical system, such as a projection optical system of a projector unit like this or an image pick-up optical system built in a camera is generally made to lie vertical relative to an image plane of an optical modulator or a photoelectric conversion light receiving element in order to reduce field curvature or other aberrations caused by a lens, and normally, the optical axis of the lens optical system is made to coincide with the center normal of the image plane of an optical modulator or light receiving element. For example, in the light receiving element, as is shown in Japanese Unexamined Patent Publication No. 2006-340299, a package is proposed in which the mounting angle of the light receiving element is made adjustable so that the light receiving element is adjusted in such a manner that the optical axis of the lens optical system becomes vertical relative to the center of a light receiving plane and is then fixed in place.